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necessary

adj. · n.
US //ˈnɛsəˌsɛɹi// UK //nˈɛsəsəɹi// nec·es·sary
  1. 1 needed (adj.)
    A2 Elementary

    needed in order to do something or to get a result.

    required or essential for a particular purpose or to achieve a specific result.

    Example

    Is it necessary to bring my passport to the bank today?

    Example

    The committee decided that a full audit was necessary before they could approve the next phase of the project.

    Usage

    Often used in the pattern 'it is necessary (for someone) to do something'.

    Pitfall
    It is necessary for you doing it.
    It is necessary for you to do it.

    The adjective 'necessary' is followed by a 'to' infinitive, not a gerund (-ing form).

  2. 2 unavoidable (adj.)
    B2 Upper Intermediate

    something that must happen and cannot be avoided.

    logically or physically inescapable; certain to occur.

    Example

    The company made some necessary changes to save money.

    Example

    While the transition was difficult, most staff agreed it was a necessary consequence of the merger.

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  1. 3 toilet (n.)
    C2 Proficiency Archaic Humorous Dialect

    an old-fashioned or funny way to talk about the toilet.

    a euphemistic term for a lavatory or outhouse.

    Example

    The old cottage still had an outdoor necessary at the back of the garden.

    Example

    In the historical novel, the characters frequently referred to the outhouse as the necessary.

    Usage

    Usually used with the definite article 'the'.

    Teacher's tip

    This sense is very rare in modern English and is mostly found in period literature or used as a joke.

Origin

From Middle English necessarye, from Old French necessaire, from Latin necessārius (“unavoidable, inevitable, required”), variant of necesse (“unavoidable, inevitable”), probably from ne or non cessum, from the perfect passive participle of cēdō (“yield; avoid, withdraw”); see cede. Older use as a noun in reference to an outhouse or lavatory under the influence of English and Latin necessārium, a medieval term for the place for monks’ “unavoidable” business, usually located behind or attached to monastic dormitories.

Word family
Idioms1 entry

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